TPS54202: Minimum input voltage at 5V output

Part Number: TPS54202

Hi team,

My customer is considering to use the TPS54202.

Could you tell me the minimum input voltage when the output voltage is 5V?

According to the d/s, TPS54202 is designed to operate at 100% duty cycle as long as the BOOT to SW pin voltage is greater than 2.1 V typically. 

I think that if the BOOT to SW pin voltage is less than 2.1V(typ), the output voltage would drop momentarily in order to turn on the low side FET.

If the input voltage is 2.1V higher than the output voltage, will the BOOT to SW pin voltage also be 2.1V higher, and will the output be regulated without dropping?　If so, minimum input voltage would be 7.1V(=5V+2.1V).

Regards,

Yamaguchi